HYBRID_DIR constant points to the directory path of the Hybrid Core framework within the theme.
Theme developers can technically name their downloaded
hybrid-core folder to whatever they want and place it as a top-level folder within their theme. This constant merely points to that folder.
This constant is only used internally by Hybrid Core to load files. There’s no reason for theme developers to make use of it.
This constant will return the directory path to the framework folder. An example of this might be the following.